cartrack: despicable: on cancelled service

I requested the service of their so called HAPPY BUTTON, which NEVER worked.

I was still billed, when I enquired, I was not given a satisfactory answer, to which i immediately cancelled the service an opted for a cancellation, which was sent via email.

I was still billed, which I reversed on both the month { I will NOT pay for a service which I did not use}. On reversal of my debit order, I am receiving countless calls and emails, during the course of the entire day, from 7am to 8pm, blocked most of the callers, and emails to the extent of me not responding anymore.

Can't they communicate amongst themselves to check that this particular service was cancelled in writing, I am so sick of their calls and services, I cannot wait for my contract to end.